1. Technical Field
The present invention relates to a method and a device for testing the water droplet shedding ability of a surface of an aircraft wing.
2. Related Art
In aviation, it is known that an ice layer may form on a wing surface when supercooled water droplets in a cloud collide with the wing surface and that icing on the wing surface may cause problems, such as decreased flight performance.
At present, a method using bleed air is one of mainstream icing prevention methods. Recently, however, a method of melting ice by heating a leading edge of a wing with an electrothermal heater, which is more fuel-efficient than the bleed-air method, has been increasingly used. However, with this method, water droplets, which are formed when ice is heated and melted, may refreeze and adhere to the wing surface after moving on the wing surface and having passed the leading edge (heated region) of the wing.
Japanese Unexamined Patent Application Publication (JP-A) 2010-234989 describes a technology in which the surface of a leading edge of a wing is a non-hydrophobic region, which is heated from the inside by using an electrothermal heater, and the surface of the remaining portion of the wing is a super-hydrophobic region. With this technology, water droplets, which are formed when ice is heated and melted at the leading edge of the wing, are shed (removed) from the wing surface due to an airflow pressure after moving on the wing surface and reaching the super-hydrophobic region.
The cross-sectional shape of an aircraft wing differs between types of aircrafts or parts of the wing.
Therefore, to evaluate an icing preventing effect of the technology described in JP-A No. 2010-234989 (that is, the water droplet shedding ability of a wing surface), it is necessary to make a wing structure that accurately simulates a wing for each of aircrafts of interest. Accordingly, it is necessary to carry out a large-scale test, including preparation.